List Custom Field Definitions

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds value by detailing what the response includes (field IDs, types, options, supported work item types), which goes beyond the annotations. No contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Single sentence that is front-loaded with the core action. No unnecessary words or repetition of schema/annotations. Efficient and to the point.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description explains the content of the response (field IDs, types, options, supported work item types). However, it does not mention pagination, ordering, or the effect of optional parameters (project_id, work_item_type) on results. Annotations partly fill the gap via openWorldHint.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description should compensate. It mentions 'for a work item type,' hinting at the work_item_type parameter, but does not explain project_id or provide details on allowable values or behavior when omitted. The parameter names are self-explanatory, but the description adds minimal extra meaning.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states it lists custom field definitions for a work item type, including specific attributes (field IDs, types, options, supported work item types). This distinguishes it from other list tools that list different resources.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies the tool is used for retrieving custom field definitions but does not explicitly state when to use it versus alternatives (e.g., list_work_items, list_labels). No when-not guidance is provided.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.